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2.4 GHz
The radio frequency range at which 802.11b, 802.11g, and Bluetooth wireless devices operate. This is also the frequency range of many household devices such as microwaves and cordless phones, which could potentially lead to interference and signal degradation.

5 GHz
The radio frequency range at which 802.11a devices operate. By using this range, devices are able to negate much of the interference that accompanies many 2.4 GHz wireless devices.

A

Adaptive Frequency Hopping (AFH)
System in which devices constantly change their operating frequency to avoid interference from other devices and maintain security. Bluetooth wireless devices use AFH to secure transfers, changing frequency 1,600 times every second. When two Bluetooth devices are "paired" they change frequencies simultaneously, while unpaired devices operate on a different frequency hopping pattern.

Ad-hoc network
A personal network created between wireless devices that doesn't require a base station. For example, two laptops can create an ad-hoc network and wirelessly transfer files directly to one another without a router or other access point.

B

Bandwidth
The maximum amount of information that can be transferred over a network in a given amount of time. It makes the most sense to think of bandwidth in terms of a river. Much like the water flow of a river is a function of the width of the river and number of obstacles, bandwidth is highest when there are few obstructions or and the information is all flowing the same direction. When multiple devices are connected to the network, the bandwidth is divided, depleting transfer rates and decreasing overall network reliability.

Bluetooth®
A short-range, wireless technology that allows devices to connect to one another and transfer information. Up to eight devices can connect to the same network (also called a piconet), and an ad-hocBluetooth network has a range of about 30 feet. Current Bluetooth wireless technology-enabled devices operate in the 2.4 GHz radio frequency range, but future versions will operate in the 6-9 GHz range, eliminating the concern of interference from other wireless devices.

C

D

E

Encryption
The process of obscuring information to make it unreadable without special knowledge. Encryption is used in wireless technology to ensure the secrecy of the information contained on the network. Bluetooth wireless technology uses adaptive frequency hopping as its form of encryption, while Wi-Fi networks require the administrator to set up the security. WPA2 is the most widely used and reliable form of encryption for personal Wi-Fi networks.

F

FireWire® (IEEE 1394 or i.Link)
Wired connection (serial bus) standard similar to, but faster than, USB. FireWire was originally developed by Apple Computers as a computer connection standard, but many devices (namely digital camcorders) feature FireWire ports beacuse of their high data transfer rates. For more information, check out our discussion of FireWire in the Connections Glossary.

G

H

I

IEEE 802.11
The official name for the Wi-Fi wireless specification. It is comprised of more than 20 different standards (802.11a, 802.11b, etc.), each of which have their own defining characteristics. Since not all standards operate on the same frequency, not all 802.11 devices are compliant with one another, so be sure to consider the compatibility when making your purchasing decision.

IEEE 802.15.1
The official name for the Bluetooth wireless specification.

J

K

L

M

Maximum theoretical transfer rate
The maximum possible rate of data transfer under optimal conditions. These numbers are used as reference points, but are not the actual transfer rates that will be experienced during typical use. (i.e. the maximum theoretical transfer rate for 802.11g certified devices is 54 Mb per second, though they typically operate at about half that speed).

Megabit (Mb)
Equivalent to about 125 kilobytes. Megabits per second (Mb/s) the standard unit of measurement for data transfer.

N

O

Operating frequency
The radio frequency range which wireless devices use to communicate with one another. Most devices use the 2.4 GHz range. (i.e. the operating frequency for 802.11g and Bluetooth is 2.4 GHz).

P

Pairing
Creating an ad-hoc personal network between two or more Bluetooth wireless enabled devices. Once devices are paired, they share the same frequency hopping pattern and are able to transfer information amongst themselves.

Piconet
A network of Bluetooth wireless devices. Devices on the same piconet share the same frequency hopping pattern and can communicate with one another without interference from devices on other piconets.

Q

R

S

Streaming media
Media that is transferred from one device to another where it is played upon arrival. The receiving device stores the information temporarily, but doesn't permanently save a copy. The faster and stronger the network connection, the more reliable the streaming process will be.

V

W

Wi-Fi®
A short-range, wireless technology that allows devices to connect to and transfer information over a local area network. Unlike Bluetooth, Wi-Fi networks require an access point to configure the network, and there is no encrpytion built into the standard.

Wi-Fi Protected Access (WPA)
The most popular encryption standard for securing Wi-Fi networks. Since Wi-Fi technology requires that users configure their own network security, users must enable WPA from a personal computer after setting up the network.

WiMAX
Based on the proposed IEEE 802.16 standards, this wireless technology could potentially allow devices to connect and transfer information at rates of up to 75 Mb/s. Coverage is currently limited to select locations but should expand in the future. WiMAX base stations, similar to cell phone towers, should have a wireless range of a few miles.

Wireless A
Another name for wireless standard 802.11a. Wireless A devices operate in the 5 GHz range and have maximum data transfer rates of 54 Mb/sec.

Wireless B
Another name for wireless standard 802.11b. Wireless B devices operate in the 2.4 GHz range and have maximum data transfer rates of 11 Mb/sec.

Wireless G
Another name for wireless standard 802.11g. Wireless G devices operate in the 2.4 GHz range and have maximum data transfer rates of 54 Mb/sec.

Wireless N
Another name for future wireless standard 802.11n. Wireless N devices will operate in the 2.4 GHz range and have maximum data transfer rates of 540 Mb/sec. The Wireless N standard has not yet been approved by the IEEE, but pre-N devices are already available for purchase.

Wireless (Wi-Fi) Access Point
A device that facilitates the creation of a Wi-Fi network. Other wireless devices connect to the network via the access point to transfer information to one another, as well as receive internet signal. Routers are the most common example of an access point.

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Crutchfield Writer Biography

Ryan Steele

Ryan grew up in Fredericksburg, Virginia and attended the University of Virginia as a Commerce candidate in the McIntire School of Commerce with a dual-concentration in Marketing and Information Technology as well as a minor in Economics. Ryan came to Crutchfield because of his passion for electronics and cutting-edge technology. During his time as the Creative Department Intern, he wrote some very helpful articles in addition to many other tasks.